The Male Reproductive System SHANDONG UNIVERSITY Liu Zhiyu

Composion: Internal genital organs Gonad-testes The duct of conveying sperms: includes Accessory glands External genital organs The Male Reproductive System Epididymes Ductus deferens duct Male urethra Scrotum Penis

internal genital organs ( 一 ) Gonad –testis Paired, ovoid organs, Located in scrotum 1.Shape Superior extremity Inferior extremity Anterior borfer Posterior border Medial surface Lateral surface

1.Shape of the testes Superior extremity inferior extremity Anterior border posterior border

tunica albuginea mediastinum testis sends numerous fibrous septules into the gland, dividing it into 100 ～ 200 testicular lobulesthat contain 2 ～ 4 contorted seminiferous tubules → traight seminiferous tubules →rete testis ( 一 ) testis 2. Structure

contorted seminiferous tubules straight seminiferous tubules rete testis

efferent ducts of testis, 12 ～ 15 in number Function of epididymis: Produces sperm secrete androgens 1.testis 2. Structure

( 二 ) Genital ducts 1. Epididymis Shape ： Comma-shaped, head of epididymis body of epididymis tail of epididymis Position ： Located on superior extremity and posterior border of testis Function – the site of accumulation and storage of sperm

Four part: 2. Ductus deferens  Testicular part － extends form the tail of epididymis to the superior extremity of testis Muscular tube that transports sperm form epididymis to ejaculatory duct

2.Ductus deferens  Spermatic part － form superior extremity of testis to the superficial inguinal ring, where the vasectomy is performed  Inguinal part － extends form superficial to deep inguinal rings

2.Ductus deferens  Pelvic part － crosses the ureter to reach the base of bladder, terminal part dilates, -----ampulla ductus deferentis

Spermatic cord Extends from the superior extremity of testis to the deep inguinal ring spermatic cord comprise: Ductus deferens Testicular artery Pampiniform plexus of vein Nerves and lymphatic vessels Vestige of vagina process

Spermatic cord These structures are enclosed by 3 layers of tunic  internal spermatic fascia  cremaster  external spermatic fascia

3.Ejaculatory duct Formed by union of distal portion ductus deferens and excretory duct of seminal vesicle Passes through the upper part of prostate and opens into the prostatic part of urethra ejaculatory duct

( 三 ) Accessory glands 1.Seminal vesicle Paired sacculated, coiled glands Secrete part of seminal fluid Located on posterior surface of bladder, lateral to ampulla ductus deferens seminal vesicle

2.Prostate position Lies behind pubic symphysis, between neck of bladder and urogenital diaphragm Shape  Chestnut-shaped organ Base of prostate Apex of prostate Body of peostate Anterior surfaces Posterior surfaces － prostatic sulcus peostate

Contains of five lobes Anterior lobe Middle lobe Posterior lobe Right and left lobes 2.Prostate Capsule of protate Sheath of protate formed by pelvic fascia

3.Bulbourethral gland － two small pea-shaped glands, located in the deep transverse muscle of perineum, opens into bulb of urethra bulbourethral gland

External genital organs ( 一 ) Scrotum Pouch of thin skin lying below the root of the penis Divided into two haves by septum of scrotum, contains testes and epididymis

External genital organs ( 一 ) Scrotum The wall of the testis consist of skin and dartos coat, a connective tissue layer that contains many smooth muscle fibers which is contineus anteriorly to the scarpa’s fascia of abdomen and posteriorly with Colles fascia of perineum

Aponeurosis of obliquus externus abdominis Obliquus internus abdominis Trasversus abdominis Transvers fascia Parietal peritoneum External spermatic fascia Cremastter Internal spermatic fascia Tunica vaginalis of testis Parietal layer Visceral layer Vaginal cavity The coverings of testis and spermatic cord

( 二 ) Penis division: root body glans penis Consists of Cavernous body of penis: 2 Cavernous body of urethra : 1

( 二 ) Penis Skin － thin and loose Prepuce of penis Frenulum of prepuce

( 三 ) Male urethra Three parts Prostatic part － lies within the prostate Membranous part– lies within the urogenital diaphragm surround by the sphincter of urethra Cavernous part － transverse the all length of cavernous body of urethra

Posterior urethra prostatic part membranous part Anterior urethra cavernous part ( 三 ) Male urethra

Three constrictions internal urethral orifice membranous part external orifice of urethra Three enlarged parts At prostatic part At bulb of urethra At navicular fossa of urethra ( 三 ) Male urethra

Two curvatures Subpubic curvature － concave upward Prepubic curvature － concave downward ( 三 ) Male urethra

Within prostatic part Urethral ridge Seminal colliculus Prostatic utricle orifices of the ejaculatory ducts ( 三 ) Male urethra

gubernaculum of tastis vagianal process vagianal ligament tunica vaginalis of tastis parietal layer visceral layer vaginal cavity

ampulla ductus deferentis

Spermatic part